This application is in response to PA-06-377 "Women's Mental Health in Pregnancy and the Postpartum Period." Recent estimates indicate that approximately 10-15 percent of women giving birth experience depression during the postpartum period (Dietz et al., 2007;Gaven et al., 2005). Research indicates that psychological interventions are efficacious for treating postpartum depression (Dennis &Hodnett, 2007). However, it is important to also focus on the prevention of postpartum depression given many women do not seek treatment (Dennis &Chung- Lee, 2006) and those who do seek treatment may have already experienced negative consequences related to depression including cessation of breastfeeding and poor maternal-child bonding (Dennis &McQueen, 2007;Murray et al., 1999). Unfortunately, research indicates that psychological interventions are not efficacious in the prevention of postpartum depression among women at risk for postpartum depression (for a review see Dennis &Creedy, 2004). Consequently, there is a need to test new and innovative interventions for the prevention of postpartum depression. Exercise interventions have been shown to be effective for the treatment of depression among adults and therefore, this intervention may be efficacious in the prevention of postpartum depression. The purpose of the present pilot study is to examine the feasibility of recruiting and retaining participants at risk for postpartum depression for a randomized trial examining an exercise intervention for the prevention of postpartum depression. We will also examine the preliminary efficacy of the exercise intervention on the prevention of postpartum depression. Specifically, 120 sedentary, healthy pregnant women who have a history of at least one depressive episode and/or have a maternal family history of depression will be recruited from various ObGyn clinics, psychiatry clinics, and via advertisements. Once the potential participants receive healthcare provider consent to exercise (approx. two weeks following a vaginal delivery and four weeks following a c-section), participants will be randomly assigned to either an exercise intervention or a health and wellness contact control condition. The exercise condition will consist of telephone-based counseling sessions designed to motivate postpartum women to become physically active. This theory-based intervention will be based on interventions shown to be effective in previous studies. The contact control condition will consist of scheduled telephone sessions with a health educator on issues related to health and wellness (e.g., stress reduction, sleep, nutrition). The specific aims of the study will be 1) to determine the feasibility of recruiting and retaining pregnant and postpartum women for an exercise inter-vention trial and 2) to determine the effect of a home-based behavioral exercise intervention on depression (as measured by the Structured Clinical Interview for DSM-IV Axis I Disorders;SCID-I and the PHQ-9) among postpartum women. Physical activity adherence will be assessed using the 7-Day Physical Activity Recall Interview (Blair et al., 1985;Sallis et al., 1985) and accelerometers (i.e., an objective assessment of physical activity). PUBLIC HEALTH RELEVANCE: Recent estimates indicate that approximately 10-15 percent of women giving birth experience depression during the postpartum period. The purpose of this study is to examine the feasibility and efficacy of an exercise intervention for the prevention of postpartum depression. If efficacious, our intervention could be disseminated in "real world settings" in an effort to prevent postpartum depression.